把这个放在div的里面可以防止div与select冲突
<iframe src="javascript:false" style="position:absolute; visibility:visible; Top:0px;Left:0px; width:1000px; height:500px; z-index:-1; filter='progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)';"></iframe>
把这个放在div的里面可以防止div与select冲突
<iframe src="javascript:false" style="position:absolute; visibility:visible; Top:0px;Left:0px; width:1000px; height:500px; z-index:-1; filter='progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)';"></iframe>
![JavaScript自学笔记【4】函数的声明与调用目录二、函数的声明 三、函数的调用[图]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)